This project has two objectives: (1) To explore the metabolic capabilities of invertebrate species, with emphasis on the ability to metabolize common environmental pollutants. Initially we are studying compounds whose metabolism is well understood in mammals, in order to make comparisons. (2) To investigate the possibility that some types of metabolism studies, especially those which must be preformed in vivo, can be effectively accomplished in species having less developed nervous systems (and are thus presumably less subject to pain and distress) than the more commonly used rodent species. We are presently studying Lumbricus terrestris, the common earthworm ("night crawler") because it has been relatively neglected in studies of metabolic capabilities, and because it i typically exposed to environmental pollutants in landfills. Most animal models for study of the effect of solar radiation on the frequency of skin cancers are either highly artificial(e.g. Nude mice) or involve animals that do not ordinarily have melanomas in the absence of promoters. The phototoxic reaction in earthworms is natural and reproducible. Studies of this phenomenon have resulted in the identification of photoactive substances in extracts of earthworms associated with potential sensitization of singlet oxygen. Similar substances occur in human skin. Our previous studies on the metabolism of phthalate plasticizers in earthworms has been completed.